E3S Web of Conferences
Volume 1, 2013Proceedings of the 16th International Conference on Heavy Metals in the Environment
|Number of page(s)
|Heavy Metals in Crops and Foods II: Terrestrial Pathways
|23 April 2013
Methylmercury Accumulation in Rice Grain (Oryza sativa L.): Environment and Genotype Controls
1 State Key Laboratory of Environmental Geochemistry, Chinese Academy of Sciences, Guiyang, China
2 Present address: University of South Carolina, Dept. of Environmental Health Sciences, Columbia, South Carolina, USA
3 State Key Laboratory of Environmental Geochemistry, Chinese Academy of Sciences, Guiyang, China
4 Guizhou Rice Research Institute, Guiyang, China
In 2010, 50 indica rice varieties were cultivated in three sites in southwestern China along a contamination gradient (background, moderately-contaminated and highly-contaminated sites) to determine environment and genotype controls on MeHg accumulation in polished white rice and bran. Rice grain MeHg concentrations were significantly higher in the moderately-contaminated site compared to the other two sites (ANOVA, p<0.0001). Lower rice grain MeHg concentrations in the highly-contaminated site possibly reflected differences in surface water pH (highly-contaminated site: pH 11, other two sites: pH 7.6-8.0). More alkaline conditions at the highly-contaminated site possibly decreased the bioavailability of MeHg and/or other trace elements, thus lowering the uptake of MeHg from paddy soil to rice grain. Polished white rice MeHg concentrations were significantly associated with rice genotype (p<0001), indicating there may be genetic markers associated with the translocation of MeHg from the maternal tissue to the filial tissue (i.e., from the bran to the polished grain). Additionally, low MeHg-accumulating rice varieties were identified, which decreased MeHg exposure up to 69%, and may be recommended to farmers to mitigate MeHg accumulation in rice grain.
Key words: methylmercury / genotype / rice / bioavailability / mitigation
© Owned by the authors, published by EDP Sciences, 2013
This is an Open Access article distributed under the terms of the Creative Commons Attribution License 2.0, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.